1. Field of the Invention
The present invention relates to an improved LED chip packaging structure, and more particular to a structure of a light emitting chip directly integrating with a substrate, thus, the present invention has the advantages of low-cost, improved heat dispersing effect, increased packaging efficiency, and enhanced competitiveness.
2. Description of Related Art
Nowadays, because the illuminating power of conventional LED has been increased, LEDs can be used as not only indicating lights or assistant lights, but also illuminating lights. Moreover, the operating current of the present high power LED may be over 2 amperes, and the operating current of conventional LEDs may be only 20 milliamperes, so that the operating current of the present high power LEDs is over 100 times larger than that of conventional LEDs, namely, the illuminating power of single high power LED is higher than a hundred of conventional LEDs. Thus, the luminance of the present high power LEDs is about 160 lumens larger than that of conventional LEDs, enabling convenient usage of power LEDs in many applications. However, the high operating current of the new high power LEDs leads to an inextricable heat dispersing problem.
Please refer to FIG. 1 showing an LED chip packaging structure 1 of a prior art. The structure includes a base 11, a supporting base 12, a chip 13, two conducting wires 14, a lens 15 and a substrate 16. Two electrode ends 111 are set on the base 11. The supporting base 12 is received in the base 11. The supporting base 12 and the base 11 are secured on a side surface of the substrate 16 via heat conducting paste 161, and the top end of the supporting base 12 contains silver adhesive 121, the chip 13 is placed on the surface of the silver adhesive 121. The two conducting wires 14 connect with the surface of chip 13 and electronically connect with the two electrode ends 111 respectively. A layer of phosphor 151 covers the outside of chip 13. The lens 15 is set on the top end of the base 11 to decrease the irradiating angles. The inside of the lens 15 is full of silica gel 152.
However, for the aforementioned LED chip packaging structure 1, the heat produced by the chip 13 cannot be directly dispersed via the substrate 16, but via the supporting base 12, the heat conducting paste 161 and the silver adhesive 121. Thus, the heat dispersing effect is bad. Moreover, the conducting wires 14 of the aforementioned LED chip packaging structure 1 is bonded by a gold wire bond, but gold wire bonds are expensive, so the users are overburdened for the high cost. Further, in the process of manufacturing the LED chip packaging structure 1, the phosphor 151 and the silica gel 152 must be respectively drying, and because the phosphor 151 and the silica gel 152 interfere the dispersion of the LED chip, as a result, the refractive index of a receiving surface of the LED chip is also interfered. Furthermore, the drying processes of the phosphor 151 and the silica gel 152 lead to low efficiency and high cost.
Moreover, there exists a double substrates structure, the chip of which is connected onto the substrates via silver adhesive, and thereby achieving a better heat dispersing effect. However, such structure must be used in the double substrates, which is also high-cost, and the manufacture efficiency cannot be increased. Thus, the market competition of the LED having such double substrates structure is lowered.
Consequently, because of the technical defects of described above, the applicant keeps on carving unflaggingly through wholehearted experience and research to develop the present invention, which can effectively improve the defects described above.